putting objects on the screen

[jargon]

Farshizzo,
thanks for the method; The reason I was thinking of attaching the ball to the screen was to possibly scale the ball manually to create a sense of the ball travelling in the +z (scale down) or -z (scale up) direction. Right now I'm using a frustum with a locked near value- this allows for left and right navigation but disallows the confusing display effects of how near or far a person is to the screen. However, the scaling is wrong based on person position and furthermore the person's position from the screen does not equal the person's virtual court position. If this all seems confusing it kind of is. Disallowing Vizard's scaling I would be able to solve this problem; However I now have a new problem- even if I can get the ball behind the net I can never really get the ball to bounce on a specific portion of the court without taking into consideration the percieved slant of the court (ie: the ball would have to bounce at varying heights depending on how far along the court in +z it was bouncing). Eh this description is terrible. Thanks for your help,
Jargon